Today's essay argues that the thing stopping clinicians from building is the fear of looking like a beginner again. Here is every Medicare-enrolled clinician in America by medical-school graduation year — 1,608,842 people, all of whom were once the first-year who didn't know what the potassium does to the EKG. Brush the timeline to isolate a cohort. Click a specialty dot to see its experience curve. The expertise in this chart is the scarce input now. Every unit of it started at zero.
CMS publishes a public file of every clinician enrolled in Medicare — with the year each one finished professional school. It is, read sideways, a census of survived beginnerhood: 1.6 million people who were all, at some point, visibly bad at the thing they now do for a living. One in six of them graduated within the last five years — they're in year one through five right now.
1,608,842
Medicare-enrolled clinicians with a graduation year
2011
median graduation year — 15 yrs ago
16.4%
graduated in the last 5 years (2021+)
19.5%
30+ years past graduation (≤1996)
The explorer
Every graduation cohort, one bar each
Bars: how many currently-enrolled clinicians graduated each year, 1950–2026. Drag across the bars to brush a cohort and the readouts recompute. Below: the 30 largest specialties, one dot each — horizontal position is the specialty's median years since graduation, dot size is headcount. Click one to reload the histogram with just that specialty; hover for its interquartile range.
Graduation-year histogram · ALL CLINICIANS
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clinicians in brush
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share of selected group
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graduation years
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years since graduation
Brush the bars to select cohorts · double-click the chart background to clear the brush. Red bars = brushed cohort.
The 30 largest specialties · x = median years since graduation · dot size = headcount · click to filter
Cardiology's median clinician is 27 years out. Nurse practitioners: 8. Same file, same room, three professional generations apart.
Read it like the essay does: pick cardiology — half its clinicians finished medical school before 1999, back when their entire current toolkit didn't exist. They learned it anyway, in public, as beginners. Now brush 2021–2026 on the all-clinicians view: ~264,000 people are in their first five years right now. Nobody is auditing the one asking beginner questions — one in six of the workforce is one.
Critical lens
What this file can't tell you
The right-edge cliff is an artifact, not a birth-rate. 2025 shows 36,629 graduates vs ~67,000 for 2019–2021. That's not fewer graduates — it's Medicare enrollment lag. Physicians spend 3–7 years in residency before most enroll; the newest cohorts simply aren't in the file yet. Brush 2024–2026 and watch the bars collapse — then don't believe your eyes.
"Years since graduation" ≠ years of independent practice.grd_yr is professional-school graduation. A surgeon 18 years out spent ~5–7 of those in training. And for NPs, PAs, PTs and social workers, it's their program's graduation year — different pipelines, not comparable apples. The NP boom at the right edge is real growth and faster enrollment after graduation, superimposed.
Medicare-enrolled only. No residents (mostly), no pure-pediatric practices, no cash-only or non-billing clinicians. This is the workforce as Medicare's billing system sees it — a very large, systematically incomplete window. Counts here will not match AAMC or licensure totals, and shouldn't.
The 80/20 read: the scarcest input in clinical software isn't engineering anymore — it's the domain expertise stacked up in this chart. But every bar in it was purchased the same way: years of being visibly, publicly new at something. The file is 1.6 million receipts for that trade. Building just asks you to make the purchase twice.